Why version() ?

[Walter Bright]

Steven Schveighoffer wrote:
> "Walter Bright" wrote
>> Denis Koroskin wrote:
>>> Does it look any better? No way!
>> Of course doing it that way doesn't look any better, because it still just 
>> replicates the C preprocessor style of doing it.
>>
>> A far better solution is to create a series of modules:
>>
>> gcnetbsd.d
>> gchurd.d
>> gcsunos5.d
>> ...
>>
>> and inside each one put the specifics for that particular system. The huge 
>> advantage of this is that if I want to create a BrightBSD operating 
>> system, I just have to write a:
>>
>> gcbrightbsd.d
> 
> All you have done is split the mess into separate files.  This does not 
> solve the problem.

How does it not solve the problem?

> 
>> rather than trying to carefully fold it into that conditional compilation 
>> mess without inadvertently breaking other platform support. (And I cannot 
>> even tell if I broke the SunOS5 platform support or not, because I don't 
>> have a SunOS5 platform to test it on.).
> 
> But you have, because inadvertently, you changed some code in the actual 
> implementation to use the new identifiers you made in your special new file. 
> Now you have to go back and rethink the sunos include because you broke it. 
> Mess still exists.  (of course, I have no idea, but I gave you as much of an 
> example/proof as you did ;)

See my example of O_APPEND for the proof that it does solve the problem 
without breaking other platforms.